Structural characterization of purine nucleoside phosphorylase from human pathogen Helicobacter pylori

Int J Biol Macromol. 2017 Aug:101:518-526. doi: 10.1016/j.ijbiomac.2017.03.101. Epub 2017 Mar 20.

Abstract

Microaerophilic bacterium Helicobacer pylori is a well known human pathogen involved in the development of many diseases. Due to the evergrowing infection rate and increase of H. pylori antibiotic resistence, it is of utmost importance to find a new way to attack and eradicate H. pylori. The purine metabolism in H. pylori is solely dependant on the salvage pathway and one of the key enzymes in this pathway is purine nucleoside phosphorylase (PNP). In this timely context, we report here the basic biochemical and structural characterization of recombinant PNP from the H. pylori clinical isolate expressed in Escherichia coli. Structure of H. pylori PNP is typical for high molecular mass PNPs. However, its activity towards adenosine is very low, thus resembling more that of low molecular mass PNPs. Understanding the molecular mechanism of this key enzyme may lead to the development of new drug strategies and help in the eradication of H. pylori.

Keywords: Crystal structure; Helicobacter pylori; Purification; Purine nucleoside phosphorylase; Stability; Substrate specificity.

MeSH terms

  • Amino Acid Sequence
  • Catalytic Domain
  • Enzyme Stability
  • Helicobacter pylori / enzymology*
  • Humans
  • Hydrogen-Ion Concentration
  • Models, Molecular
  • Protein Multimerization
  • Protein Structure, Quaternary
  • Purine-Nucleoside Phosphorylase / chemistry*
  • Purine-Nucleoside Phosphorylase / metabolism
  • Sequence Analysis
  • Substrate Specificity
  • Temperature

Substances

  • Purine-Nucleoside Phosphorylase